As I looked out the window of my office, I said out loud "It's Raining Cats and Dogs"! After I blurted it out, I started thinking of the origin of many common sayings. Like where did "It's Rain Cats and Dogs" come from. This saying actually has many different legends behind it. One legend says that in the 1500s many people lived in thatched roof homes and never kept their pets inside. In order to keep themselves warm, the cats and dogs would keep themselves hidden in the nooks of the thatching on the roofs. On days that it rained especially hard the cats and dogs would either jump or get washed off the roof...thus "It's Raining Cats and Dogs". Other Common sayings with interesting origins...."Bust Your Chops", "Rule of Thumb", "Basket Case and "Bite the Bullet", go ahead Google them...Google - where you can find "Everything But the Kitchen Sink" .